It is well known to improve the accuracy of firearms by adding weight to the firearm barrel and adjusting the weight in position lengthwise of the barrel to modulate barrel vibration or harmonics. U.S. Pat. No. 5,279,200, granted Jan. 18, 1994 to Clyde E. Rose, and entitled Ballistic Optimizing System For Rifles, discloses thread connecting a weight to a threaded muzzle of a firearm barrel and adjusting the axial position of the weight by rotating it on the threads and then locking it into the desired position by use of a lock nut which is a part of the effective added weight. The threads and the lock nut make the weight continuously and infinitely adjustable in position along the barrel.
Prior practices of attaching weights to rifle barrels for the purpose of dampening barrel vibrations are discussed in the "State of the Art" portion of U.S. Pat. No. 5,279,200. In that discussion, reference is made to U.S. Pat. No. 4,726,280, granted Feb. 23, 1988, to Guenter Frye, and entitled Mounting Of A Muzzle Member On A Gun Barrel. The muzzle member disclosed by this patent serves as a counterweight on the muzzle. The muzzle member is threaded onto the barrel and is locked in place by a lock composed of a rod positioned radially between a groove in the weight and a recess in the barrel. The prior art discussion also makes reference to barrel weights available from Anshutz and Co. G. M. P., which enable a marksman to selectively vary the amount of weight used for dampening barrel vibrations. It is also known that olympic shooters have for years attached sliding weights to rifle barrels for improving accuracy.
Muzzle brakes are also well-known in the prior art. A muzzle brake serves to reduce the recoil that is produced by the discharge of gases from the barrel after a round is fired. The muzzle brake reduces recoil by diverting some of the gases in directions which are at angles to the line of fire. The installation of a muzzle brake onto a firearm barrel inherently adds weight to the barrel. As should be apparent, if this weight is properly positioned on the barrel, it will modulate barrel vibration. U.S. Pat. No. 3,202,056, granted Aug. 24, 1965, to Curt Seeberger, and entitled Fire Arm Muzzle Brake, discloses a muzzle brake that is thread-connected to a threaded muzzle of a rifle barrel. The aforementioned U.S. Pat. No. 5,279,200 discloses a muzzle attachment that is a recognized combination muzzle brake and vibration dampener.
The muzzle attachment disclosed by U.S. Pat. No. 5,279,200 cannot be used on firearm barrels which are not threaded. Also, such attachment requires the use of a lock nut. It is well known to those skilled in the firearm art that the pressures, forces and vibrations involved at the muzzle of a firearm barrel when a round is fired are such that any member attached to the barrel must be made of high strength materials and must be securely attached. Lock nuts are not generally recognized as secure attachments unless they are safety-wired and/or tightened with appropriate tools. U.S. Pat. No. 5,279,200 makes no provision for either lock wiring or use of appropriate tools in the adjustment in position of the muzzle attachment.
There is a need for a vibration modifier that is easily adjustable in position and is securely lockable into each selected position. There is also a need for a vibration modifier that is connectable to a muzzle that is not threaded. The principal object of the present invention is provide a vibration modifier, and a combined muzzle brake and vibration modifier, which meets these needs.